Entomology Journal publishes original research papers and reviews from any entomological discipli... more Entomology Journal publishes original research papers and reviews from any entomological discipline or from directly allied fields in ecology, behavioral biology,
The present study was carried out on the newly formed pupae of the house fly Musca domestica L. (... more The present study was carried out on the newly formed pupae of the house fly Musca domestica L. (Diptera: Muscidae) to determine some biological effects of different doses of thermal neutrons. The tested pupae were subjected to 2.4 x 10 5 , 4.86 x 10 5 and9.72 x 10 5 (neutron/cm 2-S) thermal neutrons/pupa for 24 hours and to 4.86 x 10 5 , 9.72 x 10 5 and19.2 x 10 5 (neutron/cm 2-S) thermal neutrons/pupa for 48 hours. After treatment, the pupae were transferred to the rearing cages to determine any possible effects on them or on the resulting adults. There was a positive correlation between the dose level and the pupal duration, where the increase of the dose level increases the pupal duration and decreases the developmental rate. No influence on the adult emergence was detected. With increasing doses the preoviposition period increases. On the other hand, this increase decreases the oviposition period and causes a slight increase in the post oviposition period irrespective of the exposure time. A positive correlation was observed between the low doses and the fecundity, due to gonads activation, while this relationship was found to be negative at the highest dose, where it reduces it to 220 eggs/♀ and 311.6 eggs/♀ after exposure time of 24 and 48 hours, respectively compared with 370.6 eggs/♀ for control congeners. Positive fecundity inhibition percentage values were recorded at low doses. Females exposed to the highest dose showed negative responses, irrespective of the period of treatment. The fertility was also found to be slightly affected, where it declined (88.4 and 83.5 vs. 95.8 % for control) for females treated with the higher doses (9.72X10 5 and 19.2 x 10 5) for 24 and 48 hours, respectively. Finally, the sterility index had been calculated and proved the detrimental effects of the mid and high doses on the egg hatchability.
This investigation documents the presence of the alien macroalgal species Rivularia atra Roth ex ... more This investigation documents the presence of the alien macroalgal species Rivularia atra Roth ex Bornet & Flahault (Rivulariaceae: Nostocales) and Polysiphonia opaca (C. Agardh) Moris & De Notaris (Rhodomelaceae: Ceramiales) for the first time on the Libyan coastline. Of 7 investigated sites along Al-Jabel Al-Akhdar coastline during summer 2013 and winter 2014, three sites were invaded by R. atra and one site by P. opaca. The percent cover and relative frequency – as measures of abundance-of R. atra (15-24% and 40-70% respectively) were higher than those of P. opaca (8% and 17 % respectively). The investigation revealed that R. atra and P. opaca inhabited not only the rocky substrates but also the limpet Patella caerulea and that the two species do not thrive in polluted habitats. Statistical analysis showed a highly significant effect of season, site and their interaction on the physico-chemical characteristics of water. The results concluded that the nature of substrate as well as the extent of pollution may be major modifiers of algal distribution, since the non-polluted bare rocky shore was the favorite habitat for the alien species R. atra and P. opaca. Therefore, these species are promising indicators for water quality.
Red palm weevil Rhynchophorus ferrugineus. is a devastating insect pest of coconut palm, royal pa... more Red palm weevil Rhynchophorus ferrugineus. is a devastating insect pest of coconut palm, royal palm and date palm in some Asiatic and African regions. The present work dealt with the investigation of metabolic effects of azadirachtin and jojoba on the pupal stage of this pest. Three dose-levels were prepared (0.01, 0.005 and 0.001 µg/insect) and topically applied onto the prepupae. Total carbohydrate content diminished gradually by the age as a response of the medium and lowest doses of jojoba and azadirachtin. The highest dose enhanced the pupae to gain excess carbohydrates at their mid-age. Azt. showed stronger stimulatory action than jojoba for gaining carbohydrates at that age. Data indicated a remarkable depleting effect of jojoba, just after pupation, on the protein content, Neverthless, azadirachtin. induced a rise of protein content at the beginning of pupal stage, especially by the higher two dose-levels. However, jojoba and azadirachtin detrimentally suppressed the protein content in the lateaged pupae. Moreover, azadirachtin was found more potent than jojoba in such effect. After the prepupal treatment with the highest dose of jojoba, a declination of total lipid content was estimated along the pupal stage. The newly formed pupae had , generally, reduced lipids, while at the mid-age, such effect varied, depending on the extract. The lipid content decreased by jojoba but increased by azadirachtin, irrespective of the dose-level. At the late-age of pupae, their lipid contents had been diminished, regardless of the extract or its dose-level.
This study was set out to document the marine algal species associated with limpets living on the... more This study was set out to document the marine algal species associated with limpets living on the rocky shores of the north-eastern coast of Libya for the first time. Samples were collected from seven sites extend from Ras Hailal to Al-Hanyaa rocky shores during winter and spring 2012. Algal species associated with limpets in Al-Hanyaa polluted site were represented by two species belong to Chlorophyta and only one species for each Phaeophyta and Rhodophyta. On the other hand, a single species of Rhodophyta was recorded on Patella turbinata inhibiting the clean site of Susa. The present results showed that, the four algal species comprised Ulva, Enteromorpha, Ectocarpus and Gelidium, were found associated with P. turbinata and were the predominant species in polluted sites, while they disappeared completely at the clean sites. These results predicted that, Boergeseniella fruticulosa, growing either on Patella turbinata or the surrounding substrates, is a promising biomonitor for seawater cleanness. Also, the results confirmed the mutualism relationship between Patella and ephemeral algal species in the monitoring area, emphasizing their efficiency as biological monitors. Finally, in spite of physicochemical parameters differences between siteswere significant, the diference between sites themselves were found to be non significant.
Entomology Journal publishes original research papers and reviews from any entomological discipli... more Entomology Journal publishes original research papers and reviews from any entomological discipline or from directly allied fields in ecology, behavioral biology,
The present study was carried out on the newly formed pupae of the house fly Musca domestica L. (... more The present study was carried out on the newly formed pupae of the house fly Musca domestica L. (Diptera: Muscidae) to determine some biological effects of different doses of thermal neutrons. The tested pupae were subjected to 2.4 x 10 5 , 4.86 x 10 5 and9.72 x 10 5 (neutron/cm 2-S) thermal neutrons/pupa for 24 hours and to 4.86 x 10 5 , 9.72 x 10 5 and19.2 x 10 5 (neutron/cm 2-S) thermal neutrons/pupa for 48 hours. After treatment, the pupae were transferred to the rearing cages to determine any possible effects on them or on the resulting adults. There was a positive correlation between the dose level and the pupal duration, where the increase of the dose level increases the pupal duration and decreases the developmental rate. No influence on the adult emergence was detected. With increasing doses the preoviposition period increases. On the other hand, this increase decreases the oviposition period and causes a slight increase in the post oviposition period irrespective of the exposure time. A positive correlation was observed between the low doses and the fecundity, due to gonads activation, while this relationship was found to be negative at the highest dose, where it reduces it to 220 eggs/♀ and 311.6 eggs/♀ after exposure time of 24 and 48 hours, respectively compared with 370.6 eggs/♀ for control congeners. Positive fecundity inhibition percentage values were recorded at low doses. Females exposed to the highest dose showed negative responses, irrespective of the period of treatment. The fertility was also found to be slightly affected, where it declined (88.4 and 83.5 vs. 95.8 % for control) for females treated with the higher doses (9.72X10 5 and 19.2 x 10 5) for 24 and 48 hours, respectively. Finally, the sterility index had been calculated and proved the detrimental effects of the mid and high doses on the egg hatchability.
This investigation documents the presence of the alien macroalgal species Rivularia atra Roth ex ... more This investigation documents the presence of the alien macroalgal species Rivularia atra Roth ex Bornet & Flahault (Rivulariaceae: Nostocales) and Polysiphonia opaca (C. Agardh) Moris & De Notaris (Rhodomelaceae: Ceramiales) for the first time on the Libyan coastline. Of 7 investigated sites along Al-Jabel Al-Akhdar coastline during summer 2013 and winter 2014, three sites were invaded by R. atra and one site by P. opaca. The percent cover and relative frequency – as measures of abundance-of R. atra (15-24% and 40-70% respectively) were higher than those of P. opaca (8% and 17 % respectively). The investigation revealed that R. atra and P. opaca inhabited not only the rocky substrates but also the limpet Patella caerulea and that the two species do not thrive in polluted habitats. Statistical analysis showed a highly significant effect of season, site and their interaction on the physico-chemical characteristics of water. The results concluded that the nature of substrate as well as the extent of pollution may be major modifiers of algal distribution, since the non-polluted bare rocky shore was the favorite habitat for the alien species R. atra and P. opaca. Therefore, these species are promising indicators for water quality.
Red palm weevil Rhynchophorus ferrugineus. is a devastating insect pest of coconut palm, royal pa... more Red palm weevil Rhynchophorus ferrugineus. is a devastating insect pest of coconut palm, royal palm and date palm in some Asiatic and African regions. The present work dealt with the investigation of metabolic effects of azadirachtin and jojoba on the pupal stage of this pest. Three dose-levels were prepared (0.01, 0.005 and 0.001 µg/insect) and topically applied onto the prepupae. Total carbohydrate content diminished gradually by the age as a response of the medium and lowest doses of jojoba and azadirachtin. The highest dose enhanced the pupae to gain excess carbohydrates at their mid-age. Azt. showed stronger stimulatory action than jojoba for gaining carbohydrates at that age. Data indicated a remarkable depleting effect of jojoba, just after pupation, on the protein content, Neverthless, azadirachtin. induced a rise of protein content at the beginning of pupal stage, especially by the higher two dose-levels. However, jojoba and azadirachtin detrimentally suppressed the protein content in the lateaged pupae. Moreover, azadirachtin was found more potent than jojoba in such effect. After the prepupal treatment with the highest dose of jojoba, a declination of total lipid content was estimated along the pupal stage. The newly formed pupae had , generally, reduced lipids, while at the mid-age, such effect varied, depending on the extract. The lipid content decreased by jojoba but increased by azadirachtin, irrespective of the dose-level. At the late-age of pupae, their lipid contents had been diminished, regardless of the extract or its dose-level.
This study was set out to document the marine algal species associated with limpets living on the... more This study was set out to document the marine algal species associated with limpets living on the rocky shores of the north-eastern coast of Libya for the first time. Samples were collected from seven sites extend from Ras Hailal to Al-Hanyaa rocky shores during winter and spring 2012. Algal species associated with limpets in Al-Hanyaa polluted site were represented by two species belong to Chlorophyta and only one species for each Phaeophyta and Rhodophyta. On the other hand, a single species of Rhodophyta was recorded on Patella turbinata inhibiting the clean site of Susa. The present results showed that, the four algal species comprised Ulva, Enteromorpha, Ectocarpus and Gelidium, were found associated with P. turbinata and were the predominant species in polluted sites, while they disappeared completely at the clean sites. These results predicted that, Boergeseniella fruticulosa, growing either on Patella turbinata or the surrounding substrates, is a promising biomonitor for seawater cleanness. Also, the results confirmed the mutualism relationship between Patella and ephemeral algal species in the monitoring area, emphasizing their efficiency as biological monitors. Finally, in spite of physicochemical parameters differences between siteswere significant, the diference between sites themselves were found to be non significant.
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